Transcript File - Mr. Argall Online

Unit 3 Revision Points –
Physiological and
Participatory Perspectives
of Physical Activity
VCE Physical Education
Murtoa College
Monitoring and Promotion of
Physical Activity

Outcome 1 - Analysis of individual and
population levels of participation in physical
activity, and evaluate strategies that promote
adherence to the National Physical Activity
Guidelines
1. National Physical Activity Guidelines and
methods of assessing physical activity
2. Strategies for promoting physical activity and
the Social Ecological PA model
3. Promoting physical activity – settings
approaches
Chapter 1
Physiological & participatory perspectives of physical
activity

Significant health gains can be obtained from engaging in moderateintensity physical activity on most days (5 or more days) of the week.

The national guidelines for youth recommend twice the number of
minutes of physical activity per day than that recommended for adults.

It is recommended that children and youth spend less than two hours per
day using electronic media for entertainment.

To reduce the risk of falling and increase mobility, older people should
engage in strength and balance training.

To prevent weight regain once weight is lost, 60 to 90 minutes of
physical activity is recommended per day.

Physical activity can be defined as ‘any body movement produced by
the skeletal muscles that results in expenditure of energy’.
Physiological and participatory perspectives of physical activity
2

The physical activity pyramid recommends people participate in
lifestyle activities, aerobic activities and sport/rec regularly.

Sufficient activity for health may be defined as 150 minutes of
physical activity per week.

Fewer than 60 per cent of Australians engage in sufficient physical
activity for health.

According to research, only 40 per cent of Australians (15 years and
over) participate in organised sport.

Participation rates in organised sport peak between the ages of 10
and 12 years and decline throughout adolescence and adulthood.

Activity levels are lower during the winter months.
Physiological and participatory perspectives of physical activity
3

Younger children spend more time engaged in less-structured
activities (play) than older children.

Physical activity participation benefits the individual; Socially,
economically, environmentally, physically/mentally, and they generally
become healthier.

Barriers to participation include; Gender, class, income, race,
geographic location and many others.

Dimensions of physical activity that may be measured include
activity type, frequency, intensity and duration.

Energy expenditure is measured in METS (Metabolic equivalent).
Physiological and participatory perspectives of physical activity
4

The method used to assess physical activity will be determined by
whether you want to measure physical activity within large-scale
population research or among individuals.

Subjective measures of physical activity rely on a person’s recall,
whereas objective measures employ the use of a device or another
person to estimate physical activity.

Subjective examples; Self-reported recall measures, diaries and logs.

Objective examples; Direct observation (SOPLAY), HR monitors,
pedometers, accelerometers, doubly labelled water.
Multiple Choice Question
1. An example of an objective measure of physical activity is:
a.
Self report log
b.
Pedometers
c.
Personal activity level diary
d.
Recall survey
Chapter 2
Strategies for promoting physical activity & the Socio ecological Model

Determinants help us understand what factors influence physical
activity behaviour.

A mediator is the mechanism through which the intervention is
believed to influence physical activity behaviour. Effective
interventions target changes in four domains: intrapersonal, social,
physical environment and policy.

Physical activity promotional strategies are generally used at either an
individual or population level.

The choice of individual-level and/or population-level strategies to be
used will be determined by the setting and target population.

Examples of individual approaches include applying theoretical
models of individual change, counselling and print and web-based
media.
Strategies for promoting physical activity and the Stages of Change Model
2

Examples of population-level approaches include environmental change,
policy development and mass media.

Environmental change includes; Tailoring for needs, removing
impediments, building new resources and facilities, more flexible opening
hours.

Mass media campaigns include; Go for your life, 10,000 steps, find 30 and
Smart play.

Mass media employs the use of television and radio broadcasting, print
and the Internet to promote physical activity.

The Social Ecological Model consists of 4 stages that provide a
framework to assess an individual’s factors that effect their level of PA


These stages of influence are: Individual, Social, Environmental and Policy
You will need to study up exculsively on the Social Ecological Model and
how it is used to design and evaluate PA intervention strategies
Strategies for promoting physical activity and the Stages of Change Model
3

Policy may be classified as legislation and organisational policy.

Counselling options include; Telephone contact, health professionals

Cognitive strategies; increase knowledge, being aware of risks, caring
about consequences, aware of benefits, increasing opportunities to be
healthy.

Behavioural strategies; Substitute alternatives, enlisting social support,
rewards, being prepared to be active, committing yourself, reminder system.

At risk groups; Low socio-economic background, different races and ethnic
groups, disabled.
Multiple Choice Question
1. The ‘Go for your life’ program aims to:
a. Improve eating habits
b. Increase levels of physical activity
c. Promote involvement in community based programs
d. All of the above
Short Answer Question
A small rural community has low income families as large portion its
population.
The local council wants to develop a community based physical activity
intervention targeting boys aged 13-16 years.
a.
Describe two environmental changes the council could make to
encourage this group to be more active.
b.
Describe how the stages of change model could be used to
critique the effectiveness of the program.
c.
The program is designed to increase the self-efficiency of the
boys. What does this mean?
d.
What process may assist with enabling these boys to become
self-efficient?
e.
List two other ‘at-risk’ target groups (other than low income
groups).
Chapter 3
Promoting physical activity: settings-based approaches

Social, environmental and lifestyle changes over the years have
led to a gradual decline in physical activity to the extent that it is
having a detrimental effect on health.

Declining levels of physical activity is not merely about individual
behaviour.

A setting is typically a geographical area or institution containing a
large, ‘captive’ audience where health messages can be delivered
efficiently.

Possible settings in which physical activity interventions could be
adopted include community, workplace, family, transport, healthcare
and school settings.

Settings offer practical opportunities and structures for the
implementation of comprehensive strategies.
Promoting physical activity: settings-based approaches
2

A school setting has the potential to reach all children for some time in
their life and particularly provides an opportunity to reach inactive children.

The workplace represents a convenient and potentially influential
environment for fostering and encouraging physical activity.

Workplaces are recognised as key places for intervening to improve
physical activity participation and are also a suitable setting for promoting
non-recreational incidental activity such as taking the stairs.

Community settings can be broadly defined to include groups of people
from the same suburb, town, city or country.

The development of environments that make it easy to be active is an
important priority in the community setting.
Multiple Choice Questions
1. School based setting
programs result in
students:
a. Not being involved in
community sport
b. Joining sporting clubs
c. Eating unhealthily
d. Becoming more
sedentary
2. Which factor contribute to
decreased levels of
physical activity?
a. Community programs
b. More PE classes at
school
c. Reliance on technology
d. More running tracks and
skate parks
Short Answer Question
a.
b.
c.
d.
Define what is meant by a settings-based
approach as an intervention strategy in health
promotion.
Identify three settings that would be suitable
for adopting physical activity interventions.
List three examples of non-recreational
opportunities in a workplace.
Identify one community based intervention that
focuses on transport and walking.
Physiological requirements of
physical activity

1.
2.
3.
Outcome 2 - Analysis of the role and
relative contribution of the energy
systems during physical activity
Foods, fuels and energy systems
Oxygen Uptake, oxygen deficit and debt
Muscular fatigue mechanisms
Chapter 4
Foods, fuels and energy systems
1

Energy for all movements/activity comes from the breakdown of
adenosine triphosphate (ATP), which is stored at the muscles. Once
ATP is broken down, it cannot be used again until it is recharged.

The foods we eat are digested, stored and then broken down to
release energy, which allows ATP to be recharged. Phosphocreatine
is a chemical fuel stored at the muscles that can readily be broken
down to release energy and recharge ATP.

Carbohydrates are our preferred exercise fuels because they are
easier to break down than fats and proteins and require less oxygen in
the process, thus ensuring more efficient ATP production and
muscular performance.

Carbohydrates can further be classified into either low glycemic
index (GI) or high glycemic index groups. Carbohydrates that are
broken down slowly and release glucose gradually into the
bloodstream are classified as low GI.
Foods, fuels and energy systems
2

At rest, most of our energy is obtained from the breakdown of fats, but as
the workload increases so too does the amount of carbohydrate broken
down to supply energy and there is a proportionate decrease in the use of
fats.

We have three systems for making energy available to recharge ATP: two
of these systems  the ATPPC system and the Anaerobic Glycolysis
system  are anaerobic (don’t require oxygen) and the other  the Aerobic
system  is aerobic (requiring oxygen).

The ATPPC and AG systems are capable of responding immediately to
the energy demands of exercise and are suited to short, high-intensity
bursts of activity.

The three systems work together (interplay) in supplying energy for
movement, but generally one system provides the bulk of the energy
required to recharge ATP at any one time. The percentage contribution from
each system is essentially determined by the intensity and duration of the
activity.
Foods, fuels and energy systems
3

Other factors such as fatigue and recovery also need to be taken into
consideration when determining which system is the major energy provider.

The ATPPC system provides energy for explosive actions, but not for very long.
High-intensity actions can be sustained by the lactic acid system, but this is
limited by the accumulation of lactic acid. The aerobic system is the slowest to
contribute towards ATP resynthesis, but is capable of producing the most energy.
It can provide 40 to 50 times more energy than both of the anaerobic energy
systems combined.

The ATPPC system uses PC stored at the muscles for immediate energy
release. This system is limited by the amount of PC stored at the muscles – the
more intense the activity, the quicker this is used to produce ATP.

After 10 to 15 seconds, all of the PC is depleted and once this occurs this system
can no longer contribute to energy production (ATP recharge) until the athlete
rests. It takes about three minutes of total rest to fully replenish the ATPPC
system. After approximately five seconds of maximal activity, the PC stores are
40 to 50 per cent depleted and the lactic acid system becomes the major producer
of ATP.
Foods, fuels and energy systems
4

The Anaerobic Glycolysis system involves more complex recharge
reactions than the ATPPC system, and during maximal efforts takes over
at the five to 10 second mark as the major contributor to energy supply.
Peak power from this system is usually reached between five and 15
seconds and will continue to contribute to ATP production until it fatigues
(two to three minutes) due to lactic acid accumulation. This system is able
to provide twice as much energy as the ATPPC system.

The aerobic system responds quickly to the demands of intense exercise
but cannot meet energy demands during the first 10 seconds of activity. It
does not, however, take two to three minutes (as previously thought) for it to
become the major energy contributor. Recent studies have revealed that it
can provide ATP for activities above 85 per cent maximum heart rate as
early as one minute into the activity. Depending on training levels, oxygen
uptake can be as high as 90 per cent of an athlete’s maximum within 60
seconds.
Foods, fuels and energy systems
5

The difference between aerobic and anaerobic glycolysis is the
availability of oxygen.

Glycolysis deals with the breakdown of glycogen. With moderateintensity exercise, the glycogen is broken down completely to release
energy and non-fatiguing by-products such as carbon dioxide and
water.

Increased ATP demand sees glycogen being broken down to release
energy and the fatiguing by-product, lactic acid.

The lactic acid system is hence also known as the anaerobic glycolytic
system.
Multiple Choice Questions
1. High glycemic index
foods:
a. Are found in
carbohydrates that
break down quickly
b. Are found in
carbohydrates that
break down slowly
c. Keep blood glucose
levels constant
d. Lead to glycogen
sparing
2. Anaerobic glycolysis:
a. Uses both anaerobic
systems
b. Occurs in the
absence of oxygen
c. Releases more
energy than aerobic
glycolysis
d. Can continue for up
to 2 hours
Short Answer Question
You are the coach of an athlete who wishes to compete in the Murray
River Canoe Marathon.
You design a program to develop you athlete’s aerobic capacity and
anaerobic threshold.
a.
One result of the program is the relative use of fat and
carbohydrates at sub-maximal work outputs. Describe how the
relative contributions can change as a result of training.
b.
Describe how tapering training prior to the event assists the
athlete.
c.
Describe a pre race meal and a post race meal that you would
recommend for the paddler.
d.
Which energy system/s would be dominant during the marathon.
e.
Explain how the paddler is able to produce energy for work during
the event.
Chapter 5
1
Oxygen uptake, oxygen deficit and oxygen debt

During exercise, the skeletal muscle requires a constant supply of
ATP.

The nature of acute responses to exercise depends on which
muscles specifically are used; the intensity, duration and type of
activity undertaken; and how much muscle mass is involved.

There is a linear relationship between the amount of oxygen taken up
and the intensity of exercise. This relationship occurs until maximum
levels of oxygen uptake are attained (VO2 maximum).

Limitations to oxygen consumption experienced during exercise are
caused by the ability of the respiratory system to take in oxygen; the
ability of the cardiovascular system to transport and deliver oxygen to
the skeletal muscle; and the ability of the working skeletal muscle to
uptake and utilise the available oxygen.
Oxygen uptake, oxygen deficit and oxygen debt
2

When the body’s demand for oxygen exceeds the supply of oxygen
an oxygen deficit occurs.

Steady state occurs when the oxygen supplied to the body equals the
oxygen demanded by the body.

Oxygen debt is defined as the volume of oxygen used during
recovery from exercise in excess of resting oxygen consumption.

The size of the oxygen debt is proportional to the activity that has
been undertaken. Exhausting, high-intensity, anaerobic exercise
results in a larger oxygen debt than moderate aerobic exercise.

Acute responses to exercise tend to occur at the cardiovascular,
respiratory and muscular systems levels.
Oxygen uptake, oxygen deficit and oxygen debt
3

Acute responses to exercise include a reduction in creatine stores in the
active muscle, an accumulation of lactic acid, an increase in secretion of the
hormone epinephrine, a reduction in glycogen stores, an increase in muscle
temperature, and an increase and redistribution of cardiac output.

Acute responses have implications for oxygen consumption during the
activity and in the recovery phase as the body endeavours to return to preexercise levels; this is why oxygen uptake remains elevated during
recovery.

The following factors contribute to oxygen uptake remaining elevated in
recovery: increased muscle temperature, elevated levels of epinephrine, the
need to recover energy systems, restoration of creatine phosphate stores,
conversion of lactic acid to pyruvic acid, and conversion of pyruvic acid to
glucose.
Multiple Choice Questions
1. During steady state:
a. Maximal heart rate is
reached
b. Anaerobic glycolysis is
responsible for ATP
production
c. Oxygen debt and deficit
cancel each other out
d. Oxygen supply meets
oxygen demand
2. An athlete with a higher
LIP, when compared to
another athlete, would
be able to:
a. Work aerobically for
longer
b. Tolerate more lactic acid
c. Activate their aerobic
system quicker
d. Have a higher EPOC
Short Answer Question
During exercise there is a redistribution of blood
flow within the body.
a. Describe the relationship between organ and
muscle distribution once exercise has
commenced.
b. List three other acute responses to exercise.
c. What causes an increase in oxygen
consumption during exercise?
d. Are steady state and VO2 max the same
phenomenon/situation? Discuss.
e. State two reasons why EPOC occurs.
Chapter 6
Muscular fatigue mechanisms
1

After repeated contractions, a working muscle can no longer respond with
the same level of contractile activity, resulting in a loss of force and power.

The onset and rate of development of fatigue are influenced by the type of
activity being undertaken, the muscle fibre type predominantly being used,
the type of muscular contractions occurring, the intensity and duration of the
activity and the current level of fitness of the athlete.

Fatigue can be categorised as localised at the site of the working muscles,
general fatigue or long-term exhaustion (Chronic fatigue).

Depletion of glycogen and creatine phosphate, increased levels of ADP,
hydrogen ions (H+) and inorganic phosphate, reduced rates of energy
production, elevated body temperature, dehydration and changes in the
distribution of blood flow are all factors implicated in causing fatigue.
Muscular fatigue mechanisms
2

When a muscle is active, for contractile activity to continue there must be a
constant supply of ATP. As glycogen and PC stores are depleted, the
production of ATP is affected.

The metabolic consequences of producing ATP anaerobically for muscular
contraction are that ADP, lactic acid and inorganic phosphate are formed.

There is a correlation between levels of lactic acid and fatigue but lactic
acid does not cause fatigue. Hydrogen ions (H+) are directly responsible.

During exercise, blood is redistributed from other sites of the body to the
working muscles. The additional blood is used to supply oxygen and
nutrients to the muscles and to remove wastes.

Blood flow to the skin also increases as the blood vessels close to the skin
dilate to assist in eliminating heat from the body.
Muscular fatigue mechanisms
3

The body needs a certain amount of fluid to maintain all body
systems. Dehydration results when fluid loss is greater than fluid
intake.

The body has a number of mechanisms to prevent overheating in
response to the heat generated by exercise. These mechanisms
include increased sweating, vasodilation of the blood vessels near the
skin and increased blood flow to the skin.

Hot and humid conditions, increased exercise intensity and wearing
heavy clothing can all increase sweat production.

Dehydration impairs physical and mental performance, increases the
risk of injury, impairs reaction time and decision making, and
contributes to fatigue.

The symptoms of dehydration include a rapid drop in weight, thirst,
decreased amounts of urine passed, darker urine, a faster breathing
rate, weakness, light-headedness, confusion, nausea and headache.
Muscular fatigue mechanisms
4
•To avoid dehydration, it is recommended that athletes avoid starting
exercise dehydrated, drink cool water, adopt a fluid-replacement routine,
drink plenty of fluid for several hours prior to being active, drink during the
activity and drink after the activity has ceased.
•Hydration is important and no single strategy suits each player for all
environments.
•Assessing individual fluid requirements can be done by weighing yourself
before and after sport.
Multiple Choice Questions
1. An active recovery:
a. Increases venous
pooling
b. Reduces oxygen
consumption after
exercise
c. Accelerates the rate of
lactic acid metabolism
d. Causes extra fatigue
2. Glycogen depletion can
best be avoided by
consuming:
a. Low GI foods prior to an
event
b. High GI foods prior to an
event
c. Food high in fat before
an event
d. Large quantities of CHO
the night prior to the
event.
Short Answer Question
a.
b.
c.
d.
e.
f.
g.
Which line represents the athlete working at 120% VO2 max?
How is it possible to work at 120% VO2 max?
Name the dominant energy system used by the athlete at ‘intensity
B’.
What is the relationship between intensity and glycogen depletion?
How is glycogen stores best replenished?
How does lactic acid cause fatigue in the working muscle?
List three other causes of fatigue while exercising.
Multiple Choice Answers
Chapter 1
1. B
Chapter 2
1. D
Chapter 3
1. B
2. C
Chapter 4
1. A
2. B
Chapter 5
1. D
2. B
Chapter 6
1. C
2. A